1. Field of the Invention
The present invention relates to a press-clamping terminal (or crimp-type terminal) for press-fastening a sheathed wire in connecting relation thereto by press-clamping, in which whether or not a press-clamped condition is good can be easily confirmed. Further, the present invention also relates to a press-clamping terminal (or crimp-type terminal) for press-clamping a sheathed wire in connecting relation thereto by its bottom portion and press-deforming side piece portions formed respectively at opposite side edges of the bottom portion. Furthermore, the present invention also relates to a method of examining the press-clamped condition of the press-clamping terminal.
The present application is based on Japanese Patent Application Nos. 2000-175731 and 2000-175732, which are incorporated herein by reference.
2. Description of the Related Art
In the processing of the wiring in an electric system for a vehicle or the like, press-clamping terminals, formed by pressing a metal sheet into a predetermined shape, have been used to connect wires together or to connect a wire to an electrical equipment.
FIG. 1 shows such press-clamping terminals formed from a metal sheet. The plurality of press-clamping terminals 1 of a predetermined shape are formed from one metal sheet by a pressing machine (not shown) in such a manner that these terminals 1 are interconnected by a connecting plate 6, each of the press-clamping terminals 1 having a barrel 2 for press-clamping a sheathed wire in connecting relation thereto. The barrel 2 includes a pair of side piece portions 4a and 4b formed on and extending generally upright respectively from opposite side edges of a bottom portion 3 of the press-clamping terminal 1, and the barrel 2, before press-clamping the sheathed wire, has a generally U-shaped cross-section. In FIG. 1, reference numeral 5 denotes an electrical connection portion for connection to a mating terminal.
The press-clamping terminal 1 is arranged in such a manner that the bottom portion 3 of the barrel 2 is set on an anvil of a pressing apparatus, and then the sheathed wire is inserted into the barrel to be disposed on the inner surface of the bottom portion 3 in the longitudinal direction. Then, a crimper of the pressing apparatus is moved downward to curve the two side piece portions 4a and 4b of the barrel 2 inwardly in such a manner that the side piece portions 4a and 4b are opposed to the bottom portion 3, and as a result the bottom portion 3 and the side piece portions 4a and 4b press-clamp a conductor portion 7 of the sheathed wire in an embracing manner, as shown in FIG. 2.
In a first examination technique of the related art, after the conductor portion 7 is thus press-clamped, an examination is conducted to determine whether or not the press-clamping has been carried out properly. In the first examination technique, the barrel 2 is cut, and the cross-section thereof is observed, and it is judged from its cross-sectional shape whether or not the clamping is good. More specifically, when the two side piece portions 4a and 4b, press-clamping the conductor portion 7, are disposed symmetrically, this terminal is regarded as a good product.
On the other hand, when it is confirmed that the right side piece portion 4b extends into the conductor portion 7 as shown in FIG. 3A, or the left side piece portion 4a extends into the conductor portion 7 as shown in FIG. 3B, so that the two side piece portions are not disposed symmetrically, and therefore either of the two side piece portions is shifted or deviated from the proper press-clamping position (This will here in after be referred to as xe2x80x9cpress-clamping position deviationxe2x80x9d) in a direction perpendicular to the axis of the wire, it is judged that this terminal is a defective product.
During the examination, the degree of processing of the conductor is calculated from the following formula, using the above cross-sectional shape, and it is judged whether or not this conductor-processing degree is good.
Conductor-Processing Degree=(area within barrel after press-clamping÷cross-sectional area of conductor before press-clamping)xc3x97100(%)
In the first examination technique, however, the press-deformed barrel portion 2 of the press-clamping terminal 1 is cut, and whether or not the press-clamped condition is good is judged by observing its cross-sectional shape. And, the conductor-processing degree is examined by measuring the area within the barrel. Therefore, the first examination technique may encounter a problem that much time and labor have been required for the examination.
Next, the other examination techniques of the related art will be described.
FIG. 4 shows the other press-clamping terminals formed from a metal sheet. The plurality of press-clamping terminals 100 of a predetermined shape are formed from one metal sheet by a pressing machine (not shown) in such a manner that these terminals 100 are interconnected by a connecting plate 70, each of the press-clamping terminals 100 having a barrel 200 for press-clamping a sheathed wire in connecting relation thereto. The barrel 200 includes a pair of side piece portions 40a and 40b formed on and extending generally upright respectively from opposite side edges of a bottom portion 30 of the press-clamping terminal 100, and the barrel 200, before press-clamping the sheathed wire, has a generally U-shaped cross-section. In FIG. 4, reference numeral 90 denotes an electrical connection portion for connection to a mating terminal.
The press-clamping terminal 100 is arranged in such a manner that the bottom portion 30 of the barrel 200 is set on an anvil of a pressing apparatus, and then the sheathed wire is inserted into the barrel to be disposed on the inner surface of the bottom portion 30 in the longitudinal direction. Then, a crimper of the pressing apparatus is moved downward to curve the two side piece portions 40a and 40b of the barrel 200 inwardly in such a manner that the side piece portions 40a and 40b are opposed to the bottom portion 30, and as a result the bottom portion 30 and the side piece portions 40a and 40b press-clamp a conductor portion 80a of the sheathed wire 80 in an embracing manner, as shown in FIG. 5.
In this case, the sheathed wire 80 is press-clamped in such a manner that the conductor portion 80a slightly projects from a distal end of the barrel 200 as shown in FIG. 6, and bell mouths 50, which produce a locking effect as a result of expansion of the conductor portion 80a, are formed on the barrel 200. As shown in FIG. 7, serrations 60, each defined by a groove or notch of a channel-shaped cross-section, are formed in the inner surface of the bottom portion 30 of the barrel 200, and the conductor portion 80a is firmly held by this serrated portion. The bell mouths 50 and the serrations 60 serve to prevent the sheathed wire 80 from being withdrawn from the press-deformed terminal.
After the press-clamping terminal 100 is press-deformed, a press-clamped condition of the terminal is examined.
In a second examination technique, judgment is made by observing the appearance of the terminal.
However, the second examination technique may encounter the following problem. In the second technique, the press-clamped condition is judged by observing the appearance with the eyes, and therefore this judgment is liable to be subjective, and therefore there has been encountered a problem that the judgment differs from one inspector to another.
In a third technique, dimensions a and b of the bell mouths 50, formed respectively at the opposite ends of the barrel 200, are measured, and an abutment deviation of the crimper is judged from these measured values. At this time, in some cases, the cross-section is observed in order to confirm the positional relation between the serrations 60 and the press-clamped conductor portion 80a, as shown in FIG. 7.
However, the third examination technique may encounter the following problem. In the third technique, the judgment is made by measuring the dimensions a and b of the bell mouths 50, and therefore there has been encountered a problem that much labor and time are required for the examination. In the case of observing the cross-section of the serrations 60 in addition, there has been encountered a problem that more time and labor are required for the examination.
With the above problems in view, it is an object of the present invention to provide a press-clamping terminal and a method of examining the press-clamped condition of the terminal, in which a press-deformed condition can be easily examined without the need for cutting a barrel, and the examination of the press-clamped condition can be carried out effectively. Furthermore, it is another object of the present invention to provide a press-clamping terminal in which an examination can be effected quite easily, and a press-clamped condition can be accurately examined without the need for using a bulky apparatus and tools.
To achieve the above objects, according to a first aspect of the present invention, there is provided a press-clamping terminal which comprises a barrel including a bottom portion, and a pair of side piece portions, which are respectively extended from opposite side portions of the bottom portion, and between which a wire is clamped when the barrel is press-deformed; and at least one examination mark, which is deformed upon press-deforming of the barrel, formed on an outer surface of one of the bottom portion and each of the pair of side piece portions.
In accordance with the first aspect of the present invention, the examination mark, which can be deformed upon press-deforming of the barrel, is formed on the outer surface of the bottom portion or other portion. Therefore, in the examination, when the barrel is viewed from the outside thereof, the position of the mark is deviated toward either of the right and left side piece portions in accordance with the degree of press-deforming of the side piece portions, and therefore on the basis of this deviation, it can be judged whether or not either of the two side piece portions is subjected to a press-clamping position deviation. Further, the mark after the press-clamping operation is observed or measured, and the conductor-processing degree can be judged from the degree of deformation of the mark.
Therefore, by confirming the position of the mark formed on the bottom portion, the degree of deviation of the press-clamping position of the two side piece portions can be judged. And besides, by observing or measuring the size of the deformed mark, the conductor-processing degree can be judged. Therefore, it is not necessary to cut the barrel as in the technique of the related art, and the examination can be easily conducted.
Further, to achieve the above objects, according to a second aspect of the present invention, there is provided a press-clamping terminal which comprises a barrel including a bottom portion, and a pair of side piece portions, which are respectively extended from opposite side portions of the bottom portion, and between which a wire is clamped when the barrel is press-deformed; and at least one examination mark, which is deformed upon press-deforming of the barrel, stamped in an outer surface of one of the bottom portion and each of the pair of side piece portions.
In accordance with the second aspect of the present invention, since the mark is stamped in the outer surface of the bottom portion or the outer surface of the side piece portion, the mark can be formed simultaneously with the shaping of the barrel, and besides the mark will not be lost when the barrel is press-deformed, so that the bottom portion or other portion is extended, and therefore the judgment can be made positively.
According to a third aspect of the present invention, it is preferable that the examination mark has a shape symmetrical with respect to a central portion of the outer surface of one of the bottom portion and each of the pair of side piece portions.
In accordance with the third aspect of the present invention, the mark is symmetrical with respect to the axis in such a manner that its central portion coincides with the center of the bottom portion. In this case, when the mark is deviated upon press-deforming of the barrel, this deviation can be clearly confirmed with the eyes.
Further, to achieve the above objects, according to a fourth aspect of the present invention, there is provided a method of examining press-clamped condition of a press-clamping terminal including a barrel having a bottom portion and a pair of side piece portions, which are respectively extended from opposite side portions of the bottom portion, and between which a wire is clamped when the barrel is press-deformed, wherein after press-deforming the barrel to connect with the wire, press-clamped condition of the pair of side piece portions is examined. The method comprises forming an examination mark on one of the bottom portion and each of the side piece portions of the barrel in advance to press-deforming the barrel; judging a conductor processing degree of the wire on the basis of deformation of the examination mark developing upon clamping the wire; and judging a deviation degree of a press-clamping position on the pair of side piece portions in a direction perpendicular to an axis of the wire on the basis of a position of the examination mark which has been deformed.
In accordance with the fourth aspect of the present invention, in the examination, merely by observing the bottom portion of the barrel just from below the outside, the conductor-processing degree and the press-clamping position deviation of the side piece portions can be examined positively and easily.
Further, to achieve the above objects, according to a fifth aspect of the present invention, there is provided a press-clamping terminal which comprises a barrel including a bottom portion, and a pair of side piece portions, which are respectively extended from opposite side portions of the bottom portion, and between which a wire is clamped when the barrel is press-deformed; a plurality of serrations formed in an inner surface of the bottom portion of the barrel; and a plurality of grooves formed in an outer surface of the bottom portion of the barrel correspondingly to the serrations in the inner surface of the bottom portion so as to indicate positions of the serrations.
In accordance with the fifth aspect of the present invention, the respective positions of the serrations can be easily recognized from the outside of the barrel.
Further, to achieve the above objects, according to a sixth aspect of the present invention, there is provided a press-clamping terminal which comprises a barrel including a bottom portion, and a pair of side piece portions, which are respectively extended from opposite side portions of the bottom portion, and between which a wire is clamped when the barrel is press-deformed; a plurality of serrations formed in an inner surface of the bottom portion of the barrel; a plurality of grooves formed in an outer surface of the bottom portion of the barrel correspondingly to the serrations in the inner surface of the bottom portion so as to indicate positions of the serrations; and a plurality of scales, across which the grooves are respectively extended, formed on the outer surface of the bottom portion.
In accordance with the sixth aspect of the present invention, since the scales are formed, the scales can be observed from any angle, and the press-clamped condition of the barrel can be immediately confirmed.
Further, to achieve the above objects, according to a seventh aspect of the present invention, there is provided a press-clamping terminal which comprises a barrel including a bottom portion, and a pair of side piece portions, which are respectively extended from opposite side portions of the bottom portion, and between which a wire is clamped when the barrel is press-deformed; a plurality of serrations formed in an inner surface of the bottom portion of the barrel; a plurality of grooves formed in an outer surface of the bottom portion of the barrel correspondingly to the serrations in the inner surface of the bottom portion so as to indicate positions of the serrations; and a mark, across which the grooves are respectively extended, formed on the outer surface of the bottom portion.
In accordance with the seventh aspect of the present invention, for example, the mark is deformed in accordance with the press-clamped condition of the terminal, and therefore by observing the positional relation between this deformed portion and the grooves similar in shape to the serrations, it can be judged whether or not the press-clamped condition, determined by the positional relation between the press-clamping terminal and a conductor portion of the sheathed wire, is good.
Further, to achieve the above objects, according to an eighth aspect of the present invention, there is provided a press-clamping terminal which comprises a barrel including a bottom portion, and a pair of side piece portions, which are respectively extended from opposite side portions of the bottom portion, and between which a wire is clamped when the barrel is press-deformed; a plurality of serrations formed in an inner surface of the bottom portion of the barrel; a plurality of grooves, similar in shape to the serrations, stamped in an outer surface of the bottom portion of the barrel correspondingly to the serrations in the inner surface of the bottom portion so as to indicate positions of the serrations; and a mark, across which the grooves are respectively extended, stamped in the outer surface of the bottom portion.
In accordance with the eighth aspect of the present invention, for example, the grooves and the mark are stamped in the outer surface by a pressing machine or the like. In this case, the grooves and the mark can be formed simultaneously with the shaping of the barrel, and besides they will not be lost when the barrel is press-deformed.
According to a ninth aspect of the present invention, the mark may have a frame-like shape.